Polygonum aviculare L. leaves (PALs), as an important medicinal crop product, have been reported to have a strong α-glucosidase inhibitory effect. However, it is unclear which exact active compositions are primary responsible for the beneficial effects. This study showed that PALs extracted with 70 % ethanol as solvent had significantly higher total phenolic/flavonoid contents and α-glucosidase inhibitory activity than PALs extracted with other solvents. The PALs ethanol extracts showed excellent α-glucosidase inhibitory activity (IC₅₀ = 21.42 ± 1.37 μg/mL), which was significantly higher than that of anti-diabetes drug acarbose (IC₅₀ = 176.79 ± 1.72 μg/mL). The phenolic compositions of the PALs extracts were identified by high performance liquid chromatography and quadrupole-time-of-flight-mass spectrometry (HPLC-ESI-qTOF-MS/MS) method. In order to discriminate the specific α-glucosidase inhibitors from the PALs extract, an combined strategy integrating affinity ultrafiltration and HPLC-ESI-qTOF-MS/MS was developed. Seven potential α-glucosidase inhibitors with high affinity ability including orientin, myricitrin, hyperoside, isoquercitrin, o-coumaric acid, polydatin and quercetin from PALs extract were screened. The α-glucosidase inhibitory activity assay confirmed that myricitrin (IC₅₀ = 8.65 ± 1.48 μg/mL), quercetin (IC₅₀ = 15.17 ± 3.25 μg/mL), and polydatin (IC₅₀ = 35.15 ± 3.25 μg/mL) were primarily responsible for the α-glucosidase inhibitory activity of the PALs extract. Then, structure-activity relationships of these potential inhibitors were also discussed. More importantly, the possible inhibitory mechanisms of the identified inhibitors toward α-glucosidase were further clarified by molecular docking analysis. In conclusion, the proposed method can be used to effectively recognize the potential α-glucosidase inhibitors from complex extracts system in natural products.

据报道，作为重要的农作物产品，何首乌叶（PAL）具有很强的α-葡萄糖苷酶抑制作用。然而，尚不清楚哪种确切的活性组合物对有益效果起主要作用。这项研究表明，用70％乙醇作为溶剂萃取的PAL与使用其他溶剂萃取的PAL相比，具有明显更高的总酚/类黄酮含量和α-葡萄糖苷酶抑制活性。PALs乙醇提取物具有出色的α-葡萄糖苷酶抑制活性（IC ₅₀ = 21.42±1.37μg/ mL），明显高于抗糖尿病药物阿卡波糖（IC _50）。= 176.79±1.72μg/ mL）。通过高效液相色谱和四极杆飞行时间质谱（HPLC-ESI-qTOF-MS / MS）方法鉴定PAL提取物的酚类成分。为了从PAL提取物中区分出特定的α-葡萄糖苷酶抑制剂，开发了一种结合了亲和超滤和HPLC-ESI-qTOF-MS / MS的组合策略。从PALs提取物中筛选了7种潜在的具有高亲和力的α-葡萄糖苷酶抑制剂，包括Orientin，肉豆蔻酸，高苷，异槲皮苷，o-香豆酸，白蛋白和槲皮素。的α葡萄糖苷酶抑制活性测定法证实，杨梅苷（IC ₅₀ = 8.65±1.48微克/毫升），槲皮素（IC ₅₀PALs提取物的α-葡萄糖苷酶抑制活性主要归因于= 15.17±3.25μg/ mL）和多肽（IC ₅₀ = 35.15±3.25μg/ mL）。然后，还讨论了这些潜在抑制剂的构效关系。更重要的是，通过分子对接分析进一步阐明了所识别的抑制剂对α-葡萄糖苷酶的可能抑制机制。总之，该方法可用于有效识别天然产物中复杂提取物系统中潜在的α-葡萄糖苷酶抑制剂。